Telegraph-key



(No Model.)

A. P. TUCKER.

TELEGRAPH KEY.

No. 479,859. Patented Aug. 2, 1892.

, dam

UNITED STATES ALBERT F. TUCKER, OF AUBURNDALE, MASSACHUSETTS.

TELEGRAPH-KEY.

SPECIFICATION forming part of Letters Patent No. 479,859, dated August2, 1892.

Application filed March 24, 1892.

To aZZ whom it may concern.-

Be it known that I, ALBERT F. TUCKER, of Auburndale, in the county ofMiddlesex, State of Massachusetts, have invented certain new and usefulImprovements in Telegraph-Keys, of which the following is a descriptionsufficiently full, clear, and exact to enable any person skilled in theart or science to which said invention appertains to make and use thesame, reference being had to the. accompanying drawings, forming part ofthis specification, in which Figure 1 is a side elevation of my improvedkey; Fig. 2, a top plan'view of the same, and Fig. 3 a sectional viewillustrating details.

Like letters of reference indicate corresponding parts in the differentfigures of the drawings.

My invention relates especially to a selfclosing telegraph-key. Muchdifficulty is frequently experienced from the fact that switches oftelegraph-instruments in a line are accidentally left open,incapacitating the line for work until such switches are closed.

In my improved device the key is provided with an automatic switch,whereby the cir cuit is normally closed when the instrument is not inuse.

The nature and operation of the improvement will be readily understoodby all conversant with such matters from the following explanation. I

In the drawings, A represents the table, upon which the instrument ismounted. The ordinary bindingposts cl (1 for the conducting-wires passthrough the table in the usual manner and are respectively connectedwith connecting-strips b b on the face of the table, said strips beingpreferably semi-elliptical, as shown, and out of electrical contact witheach other. In lugs ff' on the plates 1) b the key-shaft gis journaled,said shaft being provided with the ordinary tension nuts. The bearing ofthe shaft in the lugs f is insulated at h, Fig. 3, from the plate 11 Thekey B is mounted on the shaft 9 and is of the ordinary generalconstruction. Its short arm is provided with the usual adjustablecontact-point 2', which normally is in engagement with the plateb. Thelong arm of the key has an adjustable screw j, against which apush-spring 7c bears, tending to elevate said arm. A projection m isformed on the plate I), and a contaetpointp on the long arm of the leveris in position to be engaged therewith in operating the key in the usualmanner.

A switch 0 comprises a lever pivoted in laterally-projecting lugs g onthe key. The long arm of the lever projects from the fingerpiece 7" ofthe key and is provided with a lip t, which may be readily engaged bythe forefinger of the operator. The opposite arm of the switch engagesthe lug f on the plate 12 and is held normally in contact therewith by apush-spring v on the key 13.

When the instrument is not in use, the circuit is closed, the currentpassing through the post (1, plate I), contact-point 2', key B, switch0, and plate 6 In manipulating the key the operator by pressing theforefinger against the lip t of the switch throws said switch laterally,disconnecting said point to from the lugf breaking the circuit.

The key in other respects is operated in the usual manner, the circuitbeing closed by depressing the key contacting the points 19 m and brokenby the elevation of the key.

Having thus explained my invention, What I claim is 1. In atelegraph-instrument, two disconnected plates respectively in electricalcontact with the line wires, a telegraph-key pivoted on said plates andinsulated from one thereof, contact-points on said key in position toalternately engage said plate, and a spring-pushed switch pivoted to thekey and normally in contact with said insulated plate, substantially asdescribed.

2. In a telegraph-instrument, the combination of the plates, as b 17respectively connected with the contact-wires, and the key B, insulatedfrom the plate 1) of the switch 0, normally in electrical contact withthe plate 12 substantially as described.-

3. In a telegraph-instrument, the combination, with the plates 1) b andmechanism for with said insulated plate, substantially as deattachingthem, respectively, to the conductscribed. ing-Wires, of the key B,pivoted on said plates and insulated from one thereof, contact- ALBERTTUCKER 5 points on said key for alternately engaging Witnesses:

said plates, and the spring-tensioned switch 0, THEODORE A. FLEU,

pivoted to said key and normally in contact JOHN C. BRUNBLECOM.

